Iiviproveivient in desulphurizing and volatilizing lead and silver ores



Pmmn JUL 41871 TLT oms.

GEORGE T. LEWIS, OYE PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN DESUIPHUIIIZING AND VULATILIZING LEAD AND SILVER DRES.

Specification forming part of Letters Patent No. 116,604, dated July 4, 1871.

To all whom t vmay concern:

Be it known that I, GEORGE T. Lnwls, of the city of Philadelphia, State of Pennsylvania, have invented a new and useful Process of Desulphurizing and Volatilizing Silver and Lead Ores, and I do hereby declare the 'ollowin is a full, clear, and exact description ot' the same, reference being had to the annexed drawin makin a part ot this specitication, in which- Figure l is a longitudinal section of' an appa- 'atus in which my process can be used, andl term it the dry process.77 Fig. 2 is a modification of the same.

The nature of my process consists in pulverizing the ore and then feedin it in small quantities into an upright ilue and forcing it through the iiame of a lateral furnace by an air-blast connected with said flue. The silver is carried by the blast of air from the blower through th e tlame, is separated, and falls to the bottom of the tlue and chambers beyond, while the lead-ore vapors pass on to collecting-bags.

To enable others skilled in the art to make and use my invention, I will describe its construction and operation.

In the drawing, A, Fig. l, is an upright tine; A', a blower; B, a lateral furnace 5 (l, the pulverized ore, whichv is fed in. proper quantities, regulated by a pair of revolving rollers, M; I), a lateral ue connecting iiue A with the tower G 5 E, the point in the iiue where silver and any undecomposed lead and silver ores are collected.

F are the bags where the lead fumes are collected.

G, G', G", &c., are intermediate towers leading between the furnace and the ba to collect the silver and to cool the lead fumes in their passa to the bags. H is a blower to increase the draught between the furnace and the I are steamjets, which steam assists in condensing the gases accompanying the fumes and assists in rendering more soluble the sulphate and sulphide of silver which are deposited in the chambers or towers. J

are iron pipes perforated with holes, which when fed with water, will create a rain or shower ot' water down the chambers or towers for the purpose ot' cooling them, besides condensing the steam, absorbing the gases, and assisting in collecting' the silver. These showers can be regulated at will in all the towers. K is a trough or box filled-with lime to receive theV overow and to decompose anysulphate or sulphide ot' silver held in solution. L is a settling cistern. As the pulverized ore C falls incontact with the iiames the lead vaporizes and pa sses over with the smoke and products of cmnbustion, its course being .marked by the arrows inthe drawing. The silver is carrie d over mechanically with the current and through the lateral iiue l) by the exhaust-blower, and drops, by reason ot' its gravity, in the tower A at E, or inthe lower parts of thetowers G, G', G, Sac,

while the lead-fumes pass along through the towers G G lI" and are caught in the closed bags F F F, where they are strained, the gases passing oitl and the oxide or salts ot' lead remaining iu the bags.

I do not limit myself to the precise form of apparatus hereinbetore given, as it may be variously modiied.

Having thus described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

Tl 1e vaporizin and desulphurizing of lea d ores bearing silver, or silver lead ores, and sepa-ratin g the silver therefrom by pulverizing the ore and submitting to the direct action of a iiame, and separating' the silver by its gravity and Solubility, and collecting the oxide or salts of lead in bags.

GEORGE T. LEWIS. Witnesses: Gnonen E. BUCKLEY, WM. It. WRIGHT. 

